The government may need to bring its 2040 ban on internal combustion cars forward to 2035 if it is to meet greenhouse gas emission targets, a new report has warned.

According to the Committee on Climate Change (CCC), the government’s Clean Growth Strategy will not be enough to hit legally binding CO2 emission targets for the 10-year period from the beginning of 2023 to the end of 2032.

The government hasn't yet clarified or even enshrined in law what exactly will be banned in 2040 – after initially appearing to say that petrol and diesel engines would be cut out entirely, ministers then seemed to row back their comments to say that internal combustion engines would be allowed in plug-in hybrid installations.

The CCC report also proposes ensuring that 60 percent of new cars and vans are powered by electric, hydrogen or plug-in hybrid powertrains by 2030, as well as targeting a 32 percent improvement in the efficiency of conventionally fuelled cars in the same time frame.

Other targets include a five percent reduction in travel demand and researching hydrogen fuel cell technology in a bid to switch HGVs away from fossil fuels.

‘As it stands, the Clean Growth Strategy does not deliver enough action to meet the UK’s emissions targets in the 2020s and 2030s,’ said CCC chairman Lord Debden. ‘The government’s policies and proposals will need to be firmed up as a matter of urgency – and supplemented with additional measures – if the UK is to deliver on its legal commitments and secure its position as an international climate change leader.’